Photoconductors that include certain photogenerating layers and specific charge transport layers are known. While these photoconductors may be useful for xerographic imaging and printing systems, a number of them have a tendency to deteriorate, and thus have to be replaced at considerable costs and with extensive resources. Also, a number of known photoconductors have a minimum of, or lack of, resistance to abrasion from dust, charging rolls, toner, and carrier. For example, the surface layers of photoconductors are subject to scratches, which decrease their lifetime, and in xerographic imaging systems adversely affect the quality of the developed images. Although used photoconductor components may be partially recycled, there continues to be added costs and potential environmental hazards when recycling. Moreover, various known photoconductors possess a combination of electrical characteristics which can be improved upon, such as improved Vr cycle up, and low dark decay properties where the Vr residual potential can increase with electrical cycling.
Thus, there is a need for photoconductors that substantially avoid or minimize the disadvantages of a number of known photoconductors.
Also, there is a need for photoconductors with extended lifetimes, reduced wearing characteristics, excellent electrical properties inclusive of high light sensitivity; stable electrical properties; low background properties; consistent Vr, residual potentials, that is substantially flat or no change in Vr, cycle up over a number of imaging cycles as illustrated by the generation of known PIDC (Photoinduced Discharge Curves), and the like, and where Vr cycle up refers to minimal residual potential increases with electrical cycling.
Further, there is a need for belt photoconductors that can be selected for high speed xerographic copying machines and printers.
There is also a need for light shock and ghost resistant photoconductors with excellent or acceptable mechanical characteristics, especially in xerographic systems where biased charging rolls (BCR) are used.
Moreover, there is a need for abrasion resistant or abrasion free, and scratch resistant or scratch free photoconductive surface layers.
Photoconductors with excellent cyclic characteristics and stable electrical properties, stable long term cycling, minimal charge deficient spots (CDS), and acceptable lateral charge migration (LCM) characteristics are also desirable needs.
Also, there is a need for photoconductors where there is prevented or minimized the oxidation of the charge transport compounds present in the charge transport layer by nitrous oxide (NOx) originating from xerographic corotron or xerographic scorotron devices.
Another need relates to the provision of photoconductors which simultaneously exhibit excellent photoinduced discharge characteristics, excellent charge/discharge cycling stability characteristics, and improved bias charge roll (BCR) wear resistance in xerographic imaging and printing systems.
These and other needs are believed to be achievable with the photoconductors disclosed herein.